let
    obj = {
        a: "aaa",
        b: "bbb"
    },
    cpobj1 = clone(obj),
    cpobj2 = JSON.parse(JSON.stringify(obj));

console.log(cpobj1);
console.log(cpobj2);


function newclone(arg) {
    let
        copy = null,
        tp = null;

    // 检测类型
    function whichType(arg) {

    }

}

function clone(obj) {
    let copy;

    // Handle the 3 simple types, and null or undefined
    if (null == obj || "object" != typeof obj) return obj;

    // Handle Date
    if (obj instanceof Date) {
        copy = new Date();
        copy.setTime(obj.getTime());
        return copy;
    }

    // Handle Array
    if (obj instanceof Array) {
        copy = [];
        for (var i = 0, len = obj.length; i < len; i++) {
            copy[i] = clone(obj[i]);
        }
        return copy;
    }

    // Handle Object
    if (obj instanceof Object) {
        copy = {};
        for (var attr in obj) {
            if (obj.hasOwnProperty(attr)) copy[attr] = clone(obj[attr]);
        }
        return copy;
    }

    throw new Error("Unable to copy obj! Its type isn't supported.");
}